test(evm): cap child_process.exec in lib.js to surface stalled commands

[wen-coding]

Summary

execCommand in contracts/test/lib.js wraps child_process.exec with no timeout. The Autobahn EVM integration matrix has hit multiple 30‑minute job timeouts where the hardhat process went silent at a test boundary, with the orphan‑process listing at cleanup consistently showing a stalled docker exec ... seid ... child still alive. The job then consumed its entire wall‑clock budget instead of surfacing a useful error.

This caps execCommand with a configurable timeout (default 60s, SIGKILL). On expiry, the rejection includes the offending command so the next occurrence is a 60s actionable error instead of a 30‑minute mystery. Override via EXEC_TIMEOUT_MS for tests that legitimately need longer.

Observed hang pattern (7 occurrences in 3 days)

Date (UTC)	Run	Affected Autobahn matrix job	Branch
05‑28 23:48	26608835541	EVM Interoperability	chore branch
05‑29 00:06	26609440164	EVM Interoperability	chore branch
05‑29 06:00	26620669539	EVM Interoperability	chore branch
05‑29 14:19	26642258916	EVM Interoperability	merge_queue #3506
05‑29 16:22	26648904362	EVM Interoperability	main push
05‑29 16:29	26648905384	EVM Interoperability	merge_queue #3511
05‑31 01:00	26699345153	EVM Module	PR #3525

Each ran for exactly ~30 minutes (job timeout). Investigation of one of the artifacts (26648905384): validators were perfectly healthy (continuing to produce blocks) the whole time, no test‑sender activity reached them during the silence — i.e., the hardhat process was alive but never sent another RPC, consistent with a stalled child process here.

Trade-off

• Healthy docker exec calls in the suite complete in ~100–200ms; 60s is comfortably above the worst observed normal case.
• If a specific test legitimately needs longer (e.g. genesis bootstrap), EXEC_TIMEOUT_MS overrides per-invocation.

Test plan

• CI: full integration matrix passes (60s is well above normal).
• The next time this stall pattern hits, the failing job will report a 60s execCommand timed out … <command> error instead of a 30‑min cancel — that error itself becomes the diagnostic.

🤖 Generated with Claude Code

[cursor]

PR Summary

Low Risk
Test-harness-only change; no production, auth, or chain logic. Risk is false timeouts on unusually slow CI steps unless EXEC_TIMEOUT_MS is raised.

Overview
Adds a wall-clock cap on execCommand in contracts/test/lib.js, which wraps every shelled-out seid / docker exec call used by the integration test helpers.

child_process.exec now runs with a 60s default timeout (SIGKILL), overridable via EXEC_TIMEOUT_MS. When Node kills the child for that timeout, failures reject with an explicit execCommand timed out after …ms message that includes a truncated command string; other kill/signal paths are left as the original error so they are not mislabeled as timeouts.

Intent: turn indefinite stalls (observed as ~30m CI job timeouts with orphaned docker exec … seid … children) into fast, actionable test failures instead of burning the whole job budget.

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[github-actions]

The latest Buf updates on your PR. Results from workflow Buf / buf (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Jun 1, 2026, 12:28 AM

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 58.30%. Comparing base (3d3df7e) to head (c1920c4).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3526      +/-   ##
==========================================
- Coverage   59.15%   58.30%   -0.85%     
==========================================
  Files        2213     2140      -73     
  Lines      182710   174341    -8369     
==========================================
- Hits       108077   101650    -6427     
+ Misses      64930    63667    -1263     
+ Partials     9703     9024     -679     

Flag	Coverage Δ
sei-db	70.41% <ø> (-0.22%)	⬇️
sei-db-state-db	?

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see 74 files with indirect coverage changes

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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[cursor]

Timeout check misattributes maxBuffer-exceeded kills as timeouts

Low Severity

The comment states error.killed is set "only when Node killed the child via the timeout option," but this is incorrect. Node's exec internally calls child.kill() for both timeout expiry and maxBuffer exceeded (ERR_CHILD_PROCESS_STDIO_MAXBUFFER), setting error.killed = true in both cases. A maxBuffer overflow would be misreported as "execCommand timed out after …", hiding the real cause. Checking error.killed && !error.code would correctly distinguish timeout (where error.code is null) from maxBuffer exceeded (where error.code is 'ERR_CHILD_PROCESS_STDIO_MAXBUFFER').

 

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